Generally, a passenger air bag refers to an air bag used for the safety of a passenger riding in a seat next to a driver, i.e., front passenger seat. The passenger air bag is an auxiliary safety system that prevents a passenger from directly contacting an instrument panel, windshield, etc. in the knees, head, chest, etc. when a vehicle collides.
Such a passenger air bag is allowed to deploy through an air bag door furnished in an instrument panel. A tear seam is often formed inside an instrument panel cover by a laser process so that the portion surrounded by the tear seam may function as an air bag door while not being recognized from the outside of the instrument panel, thereby improving interior aesthetics of the front passenger compartment.
However, the air bag is directly related to safety of the passenger, so smooth opening action of the air bag door must be secured upon deployment of the air bag. Therefore, its design requires that a passenger not be injured by the air bag door during deployment of the air bag.